Method for the solubilization of an otherwise insoluble protein

Abstract

The invention relates to a method for the solubilization, by means of ion exchanger resins, of otherwise insoluble protein expressed by cultivated cells.

What is claimed is: 
     
       1. A process for the solubilization of a protein comprising the steps of: contacting an insoluble protein expressed by cultivated cells in the form of inclusion bodies with an ion exchanger; and   separating said protein from the ion exchanger in a solubilized form whereby in the steps of contacting and separating the use of denaturing agents and detergents is excluded.   
     
     
       2. The process according to claim 1, wherein in said contacting step, said protein being in a culture broth is contacted with the ion exchanger in the presence of disrupted cells and of a cell debris. 
     
     
       3. The process according to claim 1, further comprising the step of removing disrupted cells and cell debris prior to said contacting step wherein said protein is contacted with the ion exchanger. 
     
     
       4. The process according to claim 1, wherein said ion exchanger is in the form of granules. 
     
     
       5. The process according to claim 1, wherein said ion exchanger is an anion exchanger. 
     
     
       6. The process according to claim 5, wherein said anion exchanger is Q-SEPHAROSE which comprises a gel made of 6% cross-linked agarose matrix;   an ion exchange group and a short spacer arm that attaches the group to the agarose matrix being --CH 2  --N +  (CH 3 ) 3  ; and   a counter ion being SO 4   2- .   
     
     
       7. The process according to claim 1, wherein said ion exchanger is a cation exchanger. 
     
     
       8. The process according to claim 7, wherein said cation exchanger is S-SEPHAROSE which comprises a gel made of 6% cross-linked agarose matrix;   an ion exchange group and a short spacer arm that attaches the group to the agarose matrix --CH 2  --SO 3  --; and   a counter ion being Na + .   
     
     
       9. The process according to claim 1, wherein said separating step is carried out by eluting. 
     
     
       10. The process according to claim 1, wherein a protein expressed by Escherichia coli is solubilized.